Application of Inverse Calculation Models for BOD in the Tidal Foshan River (China)

摘要

In this work, inverse calculation models of longitudinal dispersion coefficient [E(x)] and biological chemical demand (BOD) decay rate [K(x)] for the tidal Foshan River have been studied. To eliminate the morbidity of inverse calculation equations, it is not appropriate to apply conventional optimal parameter estimation methods such as discrete optimizing theory and pulse-spectrum technique to the water quality model, but modes derived in time and frequency domains can be an alternative. Therefore, the expressions of distributed E(x) and K(x) of the water quality model have been derived in both time and frequency domains, and the derivatives have been completed in different tidal current directions. This study indicates that the calculated values of BOD from the water quality models developed in the two domains for the tidal Foshan River, match the measured BOD well. In addition, due to their high anti-noise performance, the models in time domain are closer to themeasured BOD than those in frequency domain.